中华卷柏在恢复过去环境研究中的生态指示意义

Significance on ecological indication of Selaginella sinensis in reconstructing past environment

通过研究我国蕨类植物特有种中华卷柏（ Ｓｅｌａｇ ｉｎｅｌｌａ ｓｉｎｅｎｓｉｓ）在现代植被中的分布及其化石孢子在地层剖面中的时空分布规律，并阐明了中华卷柏在现代植被分布域具有连续分布的特征。在生境上，其基本生活在具有石灰质成土母质的土壤上，多生长在山坡阴处岩石上、山顶岩石上、向阳山坡石缝中、山坡灌丛下等，是一种土壤生态类型植物。在热量和水分因子上，中华卷柏生长在温度适中的区域内；多在较为湿润的地方生长。数值分析进一步表明中华卷柏的空间分布主要受年平均温度和年降雨量及地形因子的影响． 同时针对中华卷柏化石孢子的时空对比研究，指出地层剖面中出现中华卷柏指示当时环境水热因子和生境条件。

n this paper, mainly discuss the modern distribution area of Selaginella sinensis , it is a fern about 10 cm high, which is widely distributed in North ,East, Northeast, and partly in West China and it is an endemic species in China. From records offlora and species registration in herbarium Institute of Botany,to modern distribution of Selaginella sinensis ,south boundary of which distribute is Wushengguan of Hubei province (31.6°N, 113.8°E ),north boundary of which is Daxinganling ( 50.24°N , 124.07°E ), east boundary of which is Mudanjiang (44.57°N,129.60°E),west boundary of which is Helan Mts. (38.48°N,106.22°E).To moisture factor, from west to east,the annual precipitation is 397.8 1109.1 mm, Selaginella sinensis mainly distributed in semi humid places;to temperature factor, Selaginella sinensis distributed in temperate area; to altitude and topographic factors, Selagialla sinensis mainly distributed in mountain region, which grows on gentle slopes and plateaus, sunny slopes,ravines,grassing roadsides,rocks and forest gaps;to edaphic factor, Seleginella sinensis mainly grew on alkaline soil ( basic rock is the residual deposits of various limestone), it is an edaphic indicator types. Further study with analysis, distribution of Selaginella sinensis is major influenced by annual mean rainfall and annual temperature. In late Quaternary and Holocene, the distribution area of Seleginella sinensis is broader than that of modern distribution,the west boundary of fossil distribution of Selaginella sinensis being up Qinghai lakes, where annual mean temperature in Holocene might be 6℃ higher than that at present, annual mean rainfall was 100 mm higher than those at present. And now in around lake region, annual mean precipitation is about 377~399 mm, but because annual mean evaporation is 3.8 times of it, climate of Qinghai lake region is semi arid, monthly mean temperature is 12.4℃ in July, which is unavailable to growth of Selaginella sinensis .